Calculate cube roots instantly in your head

[BadgerKid]

5. These shortcuts have their place, BUT

-- not at all to go ballistic towards you -- this is exactly the type of thing that educators, scientists, and employers loathe since in and of itself, it conveys a false sense of understanding. It does help train your brain for pattern recognition, which is a nice scientific skill to have. It's good in math and computer programming because if your problem can be reduced to a solved problem, you're golden. Otherwise, you're hosed and then you need to understand how to do things the long, drawn-out way or to come up with something yourself.

My nephew likes these things; it's one of the few things that keeps his mind active and generally motivated about math.